1. Field of the Invention
The present invention relates to a method of providing, through an internet, an optimum application program for production and quality control on a printed board packaging line of a customer, based on a service providing contract with the customer.
2. Description of the Prior Art
As well known, a board packaging line for automatically packaging electronic parts or the like on a printed circuit board is configured of various processing devices including a cream solder printing device, a parts mounting device (mounter) and a reflow furnace device. Each processing device is accompanied by an inspection device for determining whether the processing result is conforming or non-conforming. In the case where a printing failure is determined by an inspection device attached to the cream solder printing device, for example, the defective board is removed from the line. In similar fashion, in the case where a part mounting defect is determined by the inspection device attached to the parts mounter, the circuit board having the particular mounting defect is removed from the line or repaired.
The cream solder printing process in the cream solder printing device has various parameters (such as the positioning accuracy, squeeze angle and the printing pressure) affecting the printing result. Also, the parts mounting process in the parts mounter has various parameters (such as the mounting accuracy, the mounting height accuracy and the mounting weight control) affecting the result of mounting the parts. In similar fashion, the reflow process in the reflow furnace device has various parameters (such as the preheating profile, the overheating profile and the temperature equalization) affecting the reflow processing result.
In the case where a given board is determined as defective after the reflow process, not only the parameters for the reflow process but also the parameters for the cream solder printing process or the parts mounting process may have had an effect. It is not an easy matter to trace the cause of the defect and take the necessary protective measures based only on the result of the board inspection after the reflow process.
In view of this, an automatic quality control system has been conventionally known, as disclosed in Japanese Unexamined Patent Publication No. 11-298200, in which the measurement data for each step with the measures taken in the past to eliminate defects are stored in a data base, and in the case where a defect occurs, the data base is accessed by use of the measurement data newly obtained. In this way, the cause involved is estimated and the required measures are taken to eliminate the defect quickly.
The development of software for estimating the defect source required to implement the automatic quality control system described above takes a vast amount of time and labor. In the manufacturing fields where the multi-item scant production is becoming the mainstay of the day, on the other hand, the system configuration of the board packaging line as well as the board to be packaged undergoes frequent changes. In addition, the boards, the electronic parts, the soldering and packaging techniques used on the board packaging line are making rapid progress every year, and there is an increasing tendency to introduce an environment-friendly material which can meet the requirements for the miniaturization and the increased number of the packaged parts. Therefore, a defect source estimation software, if developed after vigorous effort, is generally short in life.
Various software for production and quality control on the board packaging line such as the defect source estimation software described above, if introduced rapidly and inexpensively through an internet, could conveniently benefit many electronic device manufactures equipped with the board packaging line. At the same time, the provision of these software through an internet for due and assured consideration will also be of benefit to the software providers.
A system is known for providing the service in the form of software to the customer rapidly at a low operation cost through an internet. The provision of the service through the internet finds applications primarily in the field of what is called the office automation including the group schedule management and the outsourcing of the financial management. Generally, the services offered through the network have the advantages described below as compared to the method of distributing a software package off line.
The first advantage is the ease with which the application version is upgraded or the specification is changed due to the fact that the applications are managed centrally by the server. As a result, the customer can always use the latest application without special procedure, and the service provider can supply the service to the customer at a low operation cost.
The second advantage is the versatility with which the charging system and the cost burden such as the monthly fee can be changed in accordance with the actual situation of each user. As a result, the service provider can employ a variety of charging methods such as the specific charge and the fixed periodical charge. The customer can be charged satisfactorily for the real amount of the service received.
Successful development of this service provision system using the internet for an application service targeted at the board packaging line for factory automation (FA) such as “the production defect source determining service for the board packaging line” requires consideration of the situations specific to the board packaging line as described below.
According to an application program, a great amount of data including the measurements and the result of inspection from each device on a board packaging line are required to be collected and analyzed real time (first situation). The data acquired by the application program from the devices on the board packaging line may contain the manufacturing information and the manufacturing know-how highly confidential to the customer (second situation). In many cases, the manufacturing sites, where the devices on the board packaging line constituting the object of application are installed, provide an environment both unsatisfactory and expensive for internet connection (third situation). The system configuration of the production line constituting an object of application requires the removal of a given device or the replacement of a given type of device with another for adjustment of the product lines and the equipment maintenance on the part of the customer (fourth situation).
In view of the situations described above, the problem points of two conventional methods for providing the application service using the internet are described below with reference to FIG. 24.
The first conventional method is to operate an application program on a server. In this method, as shown in FIG. 24, the data acquired real time by the client software from the various devices of the board packaging line through a device driver are sent to the server through the internet so that the server executes the application program, and the result of this execution is returned to the client software in what is called “the Web computing”. The provision of the application service by this method targeted at the packaging line for factory automation poses the problem described below.
As apparent from the first situation, the data acquired from the devices on the board packaging line is vast in amount, and from the viewpoint of the communication burden, it is difficult for an application on the server to collect the data real time through the internet. An attempt to solve this problem would make it necessary for the customer to introduce a large scale of internet connection environment having a very high communication speed into the manufacturing field to receive the service.
As apparent from the second situation described above, it is problematic from the viewpoint of security for the application on the server to collect the data acquired from the various devices on the board packaging line through the internet. A security measure such as encryption of communication on the internet may be one solution, but the risk of information leakage and the anxiety on the part of the customer cannot be totally obviated.
As apparent from the first and third situations, according to this method, the customer cannot receive the service unless the client is connected to the server. To solve this problem and enable the customer to receive the service, a connection environment with the internet kept connected or the like environment is required in the manufacturing field.
The second conventional method consists in acquiring an application from the server and operating the application on the client. In this method, as shown in FIG. 24, the application is downloaded from the server and operated on the client software. This method can solve the problem of the first conventional method but still poses the problem described below.
As apparent from the third situation described above, it is difficult to remotely control from the server the operation of the application on the client software unless connected to the internet.
As apparent from the fourth situation described above, the customer is required to reinstall the application program in accordance with the system configuration of the production line each time the system configuration is changed. This requires a great number of steps and causes a trouble. The customer is required to reacquire an application program corresponding to the changed system configuration from the server. The third situation, however, makes it difficult for the customer to change the system configuration in simplistic way.
As apparent from the third situation, it is difficult for the server to carry out accurate specific charge by grasping the information unique to the application targeted at the packaging line for factory automation corresponding to, for example, the number of boards processed, the number of times a specific algorithm is executed, the monitoring time, the number of times the instruction for a specific job is issued, etc.